Pottier, J. | Search bioRxiv

bioRxiv2025

Use of massive DNA barcoding to monitor biodiversity: a test on forest soil fauna

Biodiversity monitoring primarily focuses on particular taxonomic groups for which identification expertise is widely available, such as vascular plants or birds. As a result, the response of many taxonomic groups to forest management is much less documented. With the advent of low-cost next generation barcoding approaches, it is now possible to envisage monitoring strategies based on molecular approaches, beyond metabarcoding/eDNA strategies that do not give access to species abundances and integrate species presence over largely unknown spatio-temporal scales. In this contribution, we demonstrate the use of massive DNA barcoding - also referred as megabarcoding - as a promising solution to overcome identification difficulties in demanding taxonomic groups. We performed a proof of concept study in a mountainous beech forest in the Massif Central, France. We sampled soil macrofauna at 25 sampling sites and managed to visually identify at the species level 130 out of the 1413 sampled individuals. Using megabarcoding on the 1283 remaining non-identified individuals, we managed to assign 1124 additional individuals to an operational taxonomic species at a competitive cost. We present the summary statistics of barcoding success in the different taxonomic groups encountered and in larvae versus adult individuals. We demonstrate that larvae individuals, which can hardly be visually identified at the species level, make a substantial contribution to overall macrofauna diversity. We finally showcase how this megabarcoding approach provides a concrete avenue for forest biodiversity monitoring, by assessing the cost and labour intensity of this approach.

ecology↗

bioRxiv2023

Space use of invertebrates in terestrial habitats: phylogenetic, functional and environmental drivers of interspecific variations

AimWe present the first global database of movement patterns of terrestrial invertebrates, focusing on active dispersal and foraging movements. We depict interspecific variations in movement distances among invertebrates, and assess potential drivers of these variations. LocationWorldwide. MethodsWe conducted a meta-analysis using 174 studies from the scientific literature. They provided 401 movement estimates (163 of foraging and 238 of dispersal) from 216 species, 82 families and 22 orders, complemented by the following co-variables: body mass, diet, locomotion mode, tracking method and environmental variables (gross primary productivity and mean temperature of the warmest quarter of the year). We computed allometric relationships between movement distances and body mass both globally and separately for each taxonomic order with sufficient data. We tested the relative influence of the co-variables on movement distances through model selection. ResultsWe reveal a general positive allometric relationship between movement distance and body mass that holds across most taxonomic orders. We evidence a strong phylogenetic signal in movement distances that translates in variable allometries of movement distances with body mass across taxonomic orders. We further find that interspecific variations of movement distances are primarily driven by functional differences rather than by environmental conditions. Locomotion mode appears to be the most important driver of both dispersal and foraging distances, with larger distances among flying individuals followed by walking and crawling ones for a given body mass. Trophic guild also significantly impacted movement distances with carnivores foraging further than herbivores and decomposers for most body sizes. We finally found little effect of the environmental variables tested. Main conclusionsOur study provides general allometric equations for terrestrial movement distances of invertebrates. It further reveals important functional drivers of their interspecific variation in space use with a dominant role of their evolutionary history.

ecology↗